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1.
Nature ; 590(7847): 566-570, 2021 02.
Article in English | MEDLINE | ID: mdl-33627809

ABSTRACT

When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning1; this phenomenon has been a mystery in nuclear physics for over 40 years2,3. The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum4-12. Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the γ-ray heating problem in nuclear reactors13,14, for the study of the structure of neutron-rich isotopes15,16, and for the synthesis and stability of super-heavy elements17,18.

2.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37505957

ABSTRACT

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

3.
Environ Sci Technol ; 57(47): 18690-18699, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-36946773

ABSTRACT

The kinetics of coxsackievirus serotype B5 (CVB5) inactivation with free chlorine is characterized over a range of pH and temperature relevant to drinking water treatment with the primary goal of selecting experimental conditions used for assessing inactivation mechanisms. The inactivation kinetics identified in our study is similar to or slower than experimental data reported in the literature and thus provides a conservative representation of the kinetics of CVB5 inactivation for free chlorine that could be useful in developing future regulations for waterborne viral pathogens including adequate disinfection treatment for CVB5. Untreated and free chlorine-treated viruses, and host cells synchronized-infected with these viruses, are analyzed by a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) method with the goal of quantitatively investigating the effect of free chlorine exposure on viral genome integrity, attachment to host cell, and viral genome replication. The inactivation kinetics observed results from a combination of hindering virus attachment to the host cell, inhibition of one or more subsequent steps of the replication cycle, and possibly genome damage.


Subject(s)
Disinfectants , Water Purification , Chlorine/pharmacology , Disinfectants/pharmacology , Virus Inactivation , Enterovirus B, Human , Disinfection/methods , Water Purification/methods , Kinetics
4.
Eur Arch Psychiatry Clin Neurosci ; 272(7): 1169-1181, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35802165

ABSTRACT

Deficits in social cognition and metacognition impact the course of psychosis. Sex differences in social cognition and metacognition could explain heterogeneity in psychosis. 174 (58 females) patients with first-episode psychosis completed a clinical, neuropsychological, social cognitive, and metacognitive assessment. Subsequent latent profile analysis split by sex yielded two clusters common to both sexes (a Homogeneous group, 53% and 79.3%, and an Indecisive group, 18.3% and 8.6% of males and females, respectively), a specific male profile characterized by presenting jumping to conclusions (28.7%) and a specific female profile characterized by cognitive biases (12.1%). Males and females in the homogeneous profile seem to have a more benign course of illness. Males with jumping to conclusions had more clinical symptoms and more neuropsychological deficits. Females with cognitive biases were younger and had lower self-esteem. These results suggest that males and females may benefit from specific targeted treatment and highlights the need to consider sex when planning interventions.


Subject(s)
Cognition Disorders , Metacognition , Psychotic Disorders , Cognition , Cognition Disorders/psychology , Female , Humans , Male , Psychotic Disorders/therapy , Social Cognition
5.
Environ Sci Technol ; 55(4): 2639-2651, 2021 02 16.
Article in English | MEDLINE | ID: mdl-33533604

ABSTRACT

Hydroxyapatite (HAP) is a cost-effective material to remove excess levels of fluoride from water. Historically, HAP has been considered a fluoride adsorbent in the environmental engineering community. This paper substantiates an uptake paradigm that has recently gained disparate support: assimilation of fluoride to bulk apatite lattice sites in addition to surface lattice sites. Pellets of HAP nanoparticles (NPs) were packed into a fixed-bed media filter to treat solutions containing 30 mg-F/L (1.58 mM) at pH 8, yielding an uptake of 15.97 ± 0.03 mg-F/g-HAP after 864 h. Solid-state 19F and 13C magic-angle spinning nuclear magnetic resonance spectroscopy demonstrated that all removed fluoride is apatitic. A transmission electron microscopy analysis of particle size distribution, morphology, and crystal habit resulted in the development of a model to quantify adsorption and total fluoride capacity. Low- and high-estimate median adsorption capacities were 2.40 and 6.90 mg-F/g-HAP, respectively. Discrepancies between experimental uptake and adsorption capacity indicate the range of F- that internalizes to satisfy conservation of mass. The model was developed to demonstrate that F- internalization in HAP NPs occurs under environmentally relevant conditions and as a tool to understand the extent of F- internalization in HAP NPs of any kind.


Subject(s)
Durapatite , Nanoparticles , Adsorption , Fluorides , Microscopy, Electron, Transmission
6.
Surg Radiol Anat ; 43(11): 1845-1850, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34542698

ABSTRACT

OBJECTIVE: To study the anatomical correlation between the arcuate eminence and the superior semicircular canal. MATERIAL AND METHODS: A study of the height of the arcuate eminence was carried out in 295 temporal bones. In addition, 30 temporals with different heights of the arcuate eminence (10 flat, 10 prominent and 10 very prominent) were randomly selected and radiological tests were performed by computed tomography (Pöschl projection) and subsequent dissection by milling until the apex of the superior semicircular canal was found, establishing, with both methods, the anatomical relationship with the arcuate eminence. RESULTS: The arcuate eminence was classified as: smooth, when there was no relief (1.7%); flat, measured less than 1 mm (20.3%), prominent, measured between 1 and 2 mm, in (62%), and very prominent, measured above 2 mm (12.6%). The tomographic study (CT) and its subsequent dissection by bone milling showed a direct relationship between the arcuate eminence and the semicircular canal only when it was flat, while the rest of the types corresponded to the presence of pneumatized peri-labyrinthine cells and/or cancellous bone without a direct anatomical relationship with the apex of the superior semicircular canal. CONCLUSION: The correlation between the arcuate eminence and the superior semicircular canal is direct only when it is flat (1 mm), being related to peri-labyrinthine cells and/or cancellous bone when the arcuate eminence is prominent or very prominent.


Subject(s)
Petrous Bone , Semicircular Canals , Dissection , Semicircular Canals/diagnostic imaging , Temporal Bone , Tomography, X-Ray Computed
7.
Am J Emerg Med ; 38(3): 554-561, 2020 03.
Article in English | MEDLINE | ID: mdl-31171439

ABSTRACT

BACKGROUND: Besides clinical signs and imaging, in recent years, biomarkers have proven to be a viable diagnostic resource for acute appendicitis (AA). OBJECTIVE: The objective of this study was to develop a clinical score including clinical signs and a combination of biomarkers to identify children with abdominal pain at low risk of AA. DESIGN/METHODS: We prospectively included children 2 to 14 years of age with abdominal pain suggestive of AA who presented to the emergency department between July 2016 and September 2017. A new score, the Pediatric Appendicitis Laboratory Score (PALabS) including clinical signs, leucocyte (WBC) and neutrophil (ANC) counts and plasma C-reactive protein (CRP) and calprotectin (CP) levels was developed and validated through secondary analyses of two distinct cohorts The validation sample included visits to a single pediatric emergency department from 2012 to 2013 and 2016 to 2017. RESULTS: The derivation sample included 278 children, 35.9% of whom had AA and the validation sample included 255 children, 49% of whom had AA. Using logistic regression, we created a 6-part score that consisted of nausea (3 points), history of focal right lower quadrant pain (4 points), ANC of ≥7500/µL (7 points), WBC of ≥10,000/µL (4 points), CRP ≥ 10.0 mg/L (2 points) and CP ≥ 0.50 ≥ ng/mL (3 points). This score exhibited a high discriminatory power (area under the curve: 0.88; 95% confidence interval: 0.84 to 0.92) and outperformed the PAS and Kharbanda scores (area under the curve: 0.76; 95% confidence interval: 0.71 to 0.82 and 0.82; 95% confidence interval: 0.77 to 0.87, respectively). A PALabS ≤6 had a sensitivity of 99.2% (95% confidence interval [CI]: 95.6-99.9), negative predictive value of 97.6% (95% CI: 87.7-99.6), and negative likelihood ratio of 0.03 (95% CI: 0.00-0.18) in the validation set. CONCLUSION: In our validation cohort of patients with acute abdominal pain, the new score can accurately predict which children are at low risk of appendicitis and could be safely managed with close observation.


Subject(s)
Abdominal Pain/etiology , Appendicitis/diagnosis , Risk Assessment/methods , Appendicitis/blood , Biomarkers/blood , C-Reactive Protein/metabolism , Case-Control Studies , Child , Female , Humans , Leukocyte Count , Leukocyte L1 Antigen Complex/blood , Male , Predictive Value of Tests , Prospective Studies
8.
Environ Sci Technol ; 53(2): 850-859, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30522267

ABSTRACT

In drinking water disinfection, switching from free chlorine to alternative chemical disinfectants such as monochloramine may result in the formation of different classes of toxic disinfection byproducts (DBPs). Haloacetonitriles (HANs) and haloacetamides (HAMs) are two currently unregulated nitrogen-containing DBP (N-DBP) groups commonly found in water disinfected with monochloramine that have been shown to be more cyto- and genotoxic than regulated DBPs. For the first time, this study confirms the formation of HAN and HAM dominant species found in disinfected water, dichloroacetonitrile and dichloroacetamide, from the reaction between monochloramine and dichloroacetaldehyde via the aldehyde reaction pathway. Results from experiments with natural water treated with labeled 15 N-monochloramine confirmed the relevance of the aldehyde pathway. Monochloramine reacted quickly with dichloroacetaldehyde reaching equilibrium with the carbinolamine 2,2-dichloro-1-(chloroamino)ethanol ( K1 = 1.87 × 104 M-1 s-1). Then, 2,2-dichloro-1-(chloroamino)ethanol underwent two parallel reactions where, (1) it slowly dehydrated to 1,1-dichloro-2-(chloroimino)ethane ( k2 = 1.09 × 10-5 s-1) and further decomposed to dichloroacetonitrile, and (2) it was oxidized by monochloramine ( k3 = 4.87 × 10-2 M-1 s-1) to form a recently reported N-DBP, the N-haloacetamide N,2,2-trichloroacetamide. At high pH, dichloroacetonitrile hydrolyzed to dichloroacetamide ( k40 = 3.12 × 10-7 s-1, k4OH = 3.54 M-1 s-1). Additionally, trichloroacetaldehyde was also produced from the reaction of dichloracetaldehyde and monochloramine ( k5 = 2.12 × 10-2 M-1 s-1) under the presence of monochlorammonium ion, a product of monochloramine protonation. Within the N-haloacetamide family, N,2,2-trichloroacetamide (LC50 = 3.90 × 10-4 M) was found to be more cytotoxic than N-chloroacetamide but slightly less potent than N,2-dichloroacetamide.


Subject(s)
Disinfectants , Drinking Water , Water Pollutants, Chemical , Water Purification , Chlorine , Disinfection , Halogenation
9.
Environ Sci Technol ; 52(6): 3652-3659, 2018 03 20.
Article in English | MEDLINE | ID: mdl-29480719

ABSTRACT

Polychromatic ultraviolet (UV) light with bandwidth of 20 nm and peak emission centered at 224, 254, or 280 nm (UV224, UV254, and UV280, respectively) were used to inactivate human adenovirus type 2 (HAdV-2). Quantitative polymerase chain reaction (qPCR) and reverse transcriptase qPCR assays were used to elucidate the step in the HAdV-2 replication cycle that was disrupted after UV exposure. UV treatment at any of the wavelengths analyzed did not inhibit association of HAdV-2 to the host cells even after exposure to a fluence (UV dose) that would produce a virus inactivation efficiency, measured by plaque assay, greater than 99.99%. In contrast, UV irradiation at all three peak emissions disrupted early E1A gene transcription and viral DNA replication, but different mechanisms appeared to be dominating such disruptions. UV224 seemed to have little effect on the integrity of the viral genome but produced a structural transformation of the viral capsid that may inhibit the delivery of viral genome into the host cell nucleus. On the other hand, UV254 and UV280 did not affect the integrity of the viral capsid, but the mutations they produced on the viral genome might cause the inhibition of the early gene transcription and DNA replication after the viral genome successfully translocated into the host cell nucleus.


Subject(s)
Adenoviridae Infections , Adenoviruses, Human , Adenoviridae , DNA Replication , DNA, Viral , Humans , Ultraviolet Rays , Virus Replication
10.
Article in English | MEDLINE | ID: mdl-29345622

ABSTRACT

Nasal obstruction (NO) is defined as the subjective perception of discomfort or difficulty in the passage of air through the nostrils. It is a common reason for consultation in primary and specialized care and may affect up to 30%-40% of the population. It affects quality of life (especially sleep) and lowers work efficiency. The aim of this document is to agree on how to treat NO, establish a methodology for evaluating and diagnosing it, and define an individualized approach to its treatment. NO can be unilateral or bilateral, intermittent or persistent and may be caused by local or systemic factors, which may be anatomical, inflammatory, neurological, hormonal, functional, environmental, or pharmacological in origin. Directed study of the medical history and physical examination are key for diagnosing the specific cause. NO may be evaluated using subjective assessment tools (visual analog scale, symptom score, standardized questionnaires) or by objective estimation (active anterior rhinomanometry, acoustic rhinometry, peak nasal inspiratory flow). Although there is little correlation between the results, they may be considered complementary and not exclusive. Assessing the impact on quality of life through questionnaires standardized according to the underlying disease is also advisable. NO is treated according to its cause. Treatment is fundamentally pharmacological (topical and/or systemic) when the etiology is inflammatory or functional. Surgery may be necessary when medical treatment fails to complement or improve medical treatment or when other therapeutic approaches are not possible. Combinations of surgical techniques and medical treatment may be necessary.


Subject(s)
Nasal Obstruction/drug therapy , Animals , Humans , Nasal Cavity/drug effects , Quality of Life , Rhinomanometry/methods , Rhinometry, Acoustic/methods
11.
Allergol Immunopathol (Madr) ; 46(4): 378-384, 2018.
Article in English | MEDLINE | ID: mdl-29373242

ABSTRACT

BACKGROUND: The long-term efficacy of corticosteroids to prevent atopic dermatitis (AD) relapses has partially been addressed in children. This study compared an intermittent dosing regimen of fluticasone propionate (FP) cream 0.05% with its vehicle base in reducing the risk of relapse in children with stabilized AD. METHODS: A randomized controlled, multicentric, double-blind trial was conducted. Children (2-10 years) with mild/moderate AD (exclusion criteria: >30% affected body surface area and/or head) were enrolled into an Open-label Stabilization Phase (OSP) of up to 2 weeks on twice daily FP. Those who achieved treatment success entered the Double-blind Maintenance Phase (DMP). They were randomly allocated to receive FP or vehicle twice-weekly on consecutive days for 16 weeks. The primary study endpoint was relapse rate; time to relapse and severity of disease were also studied. Kaplan-Meier estimates were calculated. RESULTS: Fifty-four patients (29 girls) entered the OSP (23 mild AD) and 49 (26 girls) continued into the DMP. Mean age was 5.5 (SD: 2.8) and 5.1 (SD: 2.3) yrs for FP and vehicle groups, respectively. Four patients withdrew from the DMP (two in every group). Patients treated with FP twice weekly had a 2.7 fold lower risk of experiencing a relapse than patients treated with vehicle (relative risk 2.72, SD: 1.28; p=0.034). FP was also superior to vehicle for delaying time to relapse. Both treatment therapies were well tolerated. CONCLUSION: This long-term study shows that twice weekly FP provides an effective maintenance treatment to control the risk of relapse in children with AD.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Dermatitis, Atopic/drug therapy , Fluticasone/therapeutic use , Secondary Prevention/methods , Child , Child, Preschool , Double-Blind Method , Female , Humans , Male
12.
J Environ Manage ; 224: 172-181, 2018 Oct 15.
Article in English | MEDLINE | ID: mdl-30041096

ABSTRACT

The addition of organic residues to soil to increase its organic matter content is considered as a viable option for sustainable food production in soils sensitive to degradation and erosion. However, the recycling of these organic residues in agricultural soils needs to be previously appraised because they can modify the behaviour of pesticides when they are simultaneously applied in agricultural practices. This study evaluated the changes in the mobility and persistence of two herbicides, triasulfuron and prosulfocarb, after two repeated applications in field experimental plots in an unamended soil and one amended with green compost (GC) for seven months. Different factors were studied: i) soil without amendment (S), ii) soil amended with two doses of GC (∼12 t C ha-1, S + GC1 and 40 t C ha-1, S + GC2), and iii) soils unamended and amended with different irrigation conditions: non-irrigated and with additional irrigation (2.8 mm per week). After the first application of herbicides, the results initially indicated no significant effects of soil treatments or irrigation conditions for triasulfuron mobility in agreement with the residual concentrations in the soil profile. The effect of irrigation was noted after one month of herbicide application and the effect of the soil treatment was significant after two months because the persistence of triasulfuron in S + GC2 was maintained until 50% of the applied amount. For prosulfocarb, the influence of soil amendment was significant for the initial persistence of the herbicide in S + GC2, higher than in S or S + GC1, in agreement with its adsorption constants for this soil. However, dissipation or leaching of the herbicide over time was not inhibited in this soil. After the repeated application of herbicides, the influence of the treatment of soils and/or irrigation was significant for the leaching and dissipation of both herbicides. The initial dissipation/degradation or leaching of herbicides was higher than after the first application, although persistence was maintained after five months of application in amended soils for triasulfuron and in unamended and amended soils for prosulfocarb. The results confirm that high doses of GC increased the persistence of both herbicides. This practice may offer the possibility of applying a tailored dose of GC to soil for striking a balance between residual concentrations and the soil agronomic effect.


Subject(s)
Herbicides , Recycling , Soil , Agriculture , Soil Pollutants
13.
J Environ Manage ; 207: 180-191, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29174993

ABSTRACT

Herbicides are essential in agricultural systems for maintaining crop yields, as weeds compromise grain production. Furthermore, the application of organic amendments to soil is an increasingly frequent agricultural practice for avoiding irreversible soil degradation. However, this practice could modify the behaviour of the herbicides applied, with implications for their absorption by weeds. This study evaluated the dissipation, persistence and mobility of the herbicides triasulfuron and prosulfocarb in a sandy clay loam soil unamended and amended with green compost (GC) in a field experiment using single or combined commercial formulations of both herbicides. The study was carried out in experimental plots (eight treatments × three replicates) corresponding to unamended soil and soil amended with GC, untreated and treated with the herbicide formulations Logran®, Auros® and Auros Plus® over 100 days. The half-life (DT50) of triasulfuron applied individually was 19.4 days, and increased in the GC-amended soil (46.7 days) due to its higher adsorption by this soil, although non-significant differences between DT50 values were found when it was applied in combination with prosulfocarb. Prosulfocarb dissipated faster than triasulfuron under all the conditions assayed, but non-significant differences were observed for the different treatments. The analysis of the herbicides at different soil depths (0-50 cm) after their application confirmed the leaching of both herbicides to deeper soil layers under all conditions, although larger amounts of residues were found in the 0-10 and 10-20 cm layers. The application of GC to the soil increased the persistence of both herbicides, and prevented the rapid leaching of triasulfuron in the soil, but the leaching of prosulfocarb was not inhibited. The influence of single or combined formulations was observed for triasulfuron, but not for prosulfocarb. The results obtained highlight the interest of obtaining field data to design rational joint applications of GC and herbicides to prevent the possible decrease in their effectiveness for weeds or the risk of water contamination.


Subject(s)
Carbamates , Composting , Soil Pollutants , Sulfonylurea Compounds , Herbicides , Soil
14.
HIV Med ; 18(8): 587-594, 2017 09.
Article in English | MEDLINE | ID: mdl-28218480

ABSTRACT

OBJECTIVES: The objective of this study was to seek correlates of immune protection in HIV infection. We sought to elucidate the association between the presence of human leucocyte antigen (HLA) alleles, as well as killer immunoglobulin receptor (KIR) genotypes, and the susceptibility to HIV infection in a Spanish cohort of HIV-exposed seronegative (HESN) individuals. METHODS: A total of 152 individuals were evaluated: 29 HESN individuals in stable heterosexual relationships with an HIV-infected partner admitting high-risk sexual intercourse for at least 12 months prior to inclusion in the study, 61 HIV-infected patients and 62 healthy controls. HLA class I and II alleles and KIR genotypes were assessed in genomic DNA from all individuals in the study by polymerase chain reaction-sequence-specific oligonucleotide (PCR-SSO) using bead array technology. RESULTS: HESN individuals showed a higher prevalence of HLA-A3 (62%) and HLA-B44 (83%) supertypes compared with HIV-infected individuals (42% and 66%, respectively). Regarding specific HLA alleles, HESN individuals had a higher prevalence of HLA-A*33:01, DRB1*04 and DQB1*03:02 alleles (14%, 34% and 31%, respectively) and a lower prevalence of the HLA-A*02:01 allele (27%) than HIV-infected patients (3%, 15%, 11% and 52%, respectively; P < 0.05). Interestingly, in a multivariate analysis, only the presence of DQB1*03:02 and the absence of A*02:01 alleles were independently associated with HESN status [odds ratio (OR) 3.4 (95% confidence interval (CI) 1.1-10.5) and 0.4 (95% CI: 0.1-0.9), respectively; P < 0.05]. No KIR genotype was associated with susceptibility to HIV infection. CONCLUSIONS: Our data showed that the presence of the HLA class II allele DQB1*03:02 was a correlate of immune protection against HIV infection, while the presence of the HLA class I allele A*02:01 was associated with being infected with HIV.


Subject(s)
Genetic Predisposition to Disease , HIV Infections/genetics , HIV Infections/immunology , HLA-A Antigens/genetics , HLA-A Antigens/metabolism , HLA-DQ beta-Chains/genetics , Adult , Aged , Alleles , Cross-Sectional Studies , Female , Genotyping Techniques , Humans , Male , Middle Aged , Receptors, KIR/genetics , Spain
15.
Biochim Biophys Acta Gen Subj ; 1861(7): 1737-1749, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28315770

ABSTRACT

The self-assembling processes underlining the capabilities of facially differentiated ("Janus") polycationic amphiphilic cyclodextrins (paCDs) as non-viral gene nanocarriers have been investigated by a pluridisciplinary approach. Three representative Janus paCDs bearing a common tetradecahexanoyl multitail domain at the secondary face and differing in the topology of the cluster of amino groups at the primary side were selected for this study. All of them compact pEGFP-C3 plasmid DNA and promote transfection in HeLa and MCF-7 cells, both in absence and in presence of human serum. The electrochemical and structural characteristics of the paCD-pDNA complexes (CDplexes) have been studied by using zeta potential, DLS, SAXS, and cryo-TEM. paCDs and pDNA, when assembled in CDplexes, render effective charges that are lower than the nominal ones. The CDplexes show a self-assembling pattern corresponding to multilamellar lyotropic liquid crystal phases, characterized by a lamellar stacking of bilayers of the CD-based vectors with anionic pDNA sandwiched among them. When exposed to human serum, either in the absence or in the presence of pDNA, the surface of the cationic CD-based vector becomes coated by a protein corona (PC) whose composition has been analyzed by nanoLC-MS/MS. Some of the CDplexes herein studied showed moderate-to-high transfection levels in HeLa and MCF-7 cancer cells combined with moderate-to-high cell viabilities, as determined by FACS and MTT reduction assays. The ensemble of data provides a detail picture of the paCD-pDNA-PC association processes and a rational base to exploit the protein corona for targeted gene delivery on future in vivo applications.


Subject(s)
Cyclodextrins/chemistry , DNA/chemistry , Protein Corona/chemistry , Transfection/methods , Biophysics , HeLa Cells , Humans , MCF-7 Cells , Nanoparticles
16.
Environ Sci Technol ; 51(24): 14352-14359, 2017 Dec 19.
Article in English | MEDLINE | ID: mdl-29156131

ABSTRACT

Two-dimensional covalent organic frameworks (COFs) were used to create the first asymmetric, thin-film composite (TFC) nanofiltration (NF) membrane with a COF active layer. NF membrane active layers of polyimine COF were synthesized via the interfacial polymerization (IP) of terephthalaldehyde and tris(4-aminophenyl)benzene monomers on top of a poly(ether sulfone) (PES) ultrafiltration membrane support. Rutherford backscattering spectrometry and Fourier transform infrared spectroscopy analyses confirmed the presence of an imine-linked film with a thickness of ∼10 nm that was formed reproducibly. The rejection efficiencies of the COF NF membrane for a model organic compound, Rhodamine-WT, and a background electrolyte, NaCl, were higher than those of the PES support without the COF film. This enhanced solute rejection is the first successful demonstration of a TFC membrane with a thin COF active layer. However, this work also demonstrates the need for COF NF membranes with smaller active layer pores and alternative support materials. The former should result in greater solute rejection, and the latter is key because the PES used for support in the COF membranes is incompatible with the organic solvents used for the COF IP process.


Subject(s)
Metal-Organic Frameworks , Solvents , Membranes, Artificial , Organic Chemicals , Polymerization , Water Purification
17.
Ecotoxicol Environ Saf ; 139: 454-462, 2017 May.
Article in English | MEDLINE | ID: mdl-28213322

ABSTRACT

Lignocellulosic wastes and by-products containing lignin are now available in large amounts from forestry and industrial activities, and could be promising organic materials for the biosorption of pesticides by soils in order to reduce point-source pollution. Adding these materials to soil requires understanding the process of pesticide sorption-desorption by wood-soils, as sorption capacity could increase, with changes in pesticide bioavailability and final fate. The objective of this work was to study the effect that pine and oak wood added to soils had on the sorption/desorption of the pesticides linuron, alachlor, and metalaxyl. Experiments were conducted with two sandy loam and sandy clay soils each amended with two wood doses (5% and 50%) after different incubation times (0, 5 and 12 months). A low wood dose (5%) had no significant impact on the sorption (Kf) of alachlor, but Kf increased for linuron (up to 5.4-1.7 times) and metalaxyl (up to 4.4 and 8.6 times) in all wood-soil systems. The results were not significantly different after different incubation times. The desorption results indicated that wood decreases the sorption irreversibility of alachlor, and increases that of linuron and metalaxyl, with a varying effect of the wood-soil incubation time. The addition of a high wood dose to soil (50%) was more significant for increasing the sorption of all the pesticides, and the sorbed amounts remaining after desorption (>49% for linuron, >33% for alachlor and >6% for metalaxyl), although there was no apparent discrimination between the two types of woods. The role of the nature of the organic carbón (Koc values) for sorption was evidenced for alachlor and metalaxyl, but not for linuron. These outcomes are of interest for extending wood application to soil as a barrier for avoiding environmental risk by point-source pollution due to the use and management of pesticides in farming systems.


Subject(s)
Pesticides/analysis , Soil Pollutants/analysis , Soil , Wood , Acetamides/analysis , Adsorption , Alanine/analogs & derivatives , Alanine/analysis , Linuron/analysis
18.
Allergol Immunopathol (Madr) ; 45(4): 369-374, 2017.
Article in English | MEDLINE | ID: mdl-28238404

ABSTRACT

INTRODUCTION: Allergic diseases affect 15-20% of the paediatric population in the industrialised world. Most educational centres in Spain do not have health professionals among their staff, and the teachers are in charge of child care in school. The advisability of specific training of the teaching staff should be considered, with the introduction of concrete intervention plans in the event of life-threatening emergencies in schools. MATERIAL AND METHODS: Evaluation of the training needs constitutes the first step in planning an educational project. In this regard, the Health Education Group of the Spanish Society of Clinical Immunology, Allergology and Paediatric Asthma (Grupo de Educación Sanitaria de la Sociedad Española de Inmunología Clínica, Alergología y Asma Pediátrica [SEICAAP]) assessed the knowledge of teachers in five Spanish Autonomous Communities, using a self-administered questionnaire specifically developed for this study. The data obtained were analysed using the SPSS statistical package. RESULTS: A total of 2479 teachers completed the questionnaire. Most of them claimed to know what asthma is, and almost one half considered that they would know how to act in the event of an asthma attack. This proportion was higher among physical education teachers. Most would not know how to act in the case of anaphylaxis or be able to administer the required medication. In general, the teachers expressed interest in receiving training and in having an interventional protocol applicable to situations of this kind. DISCUSSION: It is important to know what the training requirements are in order to develop plans for intervention in the event of an emergency in school. Teachers admit a lack of knowledge on how to deal with these disorders, but express a wish to receive training.


Subject(s)
Anaphylaxis/epidemiology , Asthma/epidemiology , Hypersensitivity/epidemiology , School Teachers , Adult , Emergency Medical Services , Female , Guidelines as Topic , Health Education , Health Knowledge, Attitudes, Practice , Humans , Male , Physical Education and Training , Spain/epidemiology , Surveys and Questionnaires
19.
J Struct Biol ; 195(1): 123-8, 2016 07.
Article in English | MEDLINE | ID: mdl-27102900

ABSTRACT

Macromolecular complexes perform their physiological functions by local rearrangements of their constituents and biochemically interacting with their reaction partners. These rearrangements may involve local rotations and the induction of local strains causing different mechanical efforts and stretches at the different areas of the protein. The analysis of these local deformations may reveal important insight into the way proteins perform their tasks. In this paper we introduce a method to perform this kind of local analysis using Electron Microscopy volumes in a fully objective and automatic manner. For doing so, we exploit the continuous nature of the result of an elastic image registration using B-splines as its basis functions. We show that the results obtained by the new automatic method are consistent with previous observations on these macromolecules.


Subject(s)
Macromolecular Substances/chemistry , Microscopy, Electron/methods , Adenosine Triphosphate/chemistry , Algorithms , Automation , Bacterial Proteins/chemistry , Biomechanical Phenomena , Chaperonin 60/chemistry , Heat-Shock Proteins/chemistry , Humans , Mitochondrial Ribosomes/chemistry , Models, Theoretical , Molecular Chaperones/chemistry , Protein Binding , Rotation
20.
Environ Sci Technol ; 50(5): 2522-9, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26820824

ABSTRACT

Elucidating mechanisms by which pathogenic waterborne viruses become inactivated by drinking water disinfectants would facilitate the development of sensors to detect infectious viruses and novel disinfection strategies to provide safe water. Using bacteriophages as surrogates for human pathogenic viruses could assist in elucidating these mechanisms; however, an appropriate viral surrogate for human adenovirus (HAdV), a medium-sized virus with a double-stranded DNA genome, needs to be identified. Here, we characterized the inactivation kinetics of bacteriophage PR772, a member of the Tectiviridae family with many similarities in structure and replication to HAdV. The inactivation of PR772 and HAdV by free chlorine had similar kinetics that could be represented with a model previously developed for HAdV type 2 (HAdV-2). We developed and tested a quantitative assay to analyze several steps in the PR772 replication cycle to determine if both viruses being inactivated at similar rates resulted from similar replication cycle events being inhibited. Like HAdV-2, we observed that PR772 inactivated by free chlorine still attached to host cells, and viral DNA synthesis and early and late gene transcription were inhibited. Consequently, free chlorine exposure inhibited a replication cycle event that was post-binding but took place prior to early gene synthesis for both PR772 and HAdV-2.


Subject(s)
Adenoviruses, Human/drug effects , Bacteriophages/drug effects , Chlorine/pharmacology , Water Purification/methods , Adenoviruses, Human/physiology , Bacteriophages/genetics , Bacteriophages/physiology , Disinfectants/pharmacology , Disinfection/methods , Kinetics , Polymerase Chain Reaction/methods , Virus Replication/drug effects , Water Microbiology
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